Objective The distribution and morphology of 5-HT immunoreactive endocrine cells in the digestive tract of Lacerta vivipara Jacquin were investigated.Methods ABC immunohistochemical technique was applied.Results The 5-HT cells distributed throughout the digestive tract,from esophagus to rectum.The distribution density curve appeared waveform and there were three density peaks: cardiac part of the stomach,pylorus of the stomach and ileum.The 5-HT cells were round, ellipse,shuttle-like or tapering in shape,mainly round and ellipse,and distributed widely at the basal region of epithelium,between glandular epithelial cells and between acini.Conclusion In view of their morphology we would suggest that 5-HT cells have both endocrine and exocrine functions. A comparison of the distribution density of 5-HT cells in the digestive tract between sevtral few reptiles suggest that the difference of their distribution density might be related to feeding habit and surroundings as well.